feat(healthcheck): adding healthcheck module

Author: gergelyke

lib/agent/api/index.js

@@ -17,6 +17,7 @@ function CollectorApi (options) {
   this.COLLECTOR_API_RPM_METRICS = url.resolve(options.collectorApiUrl, options.collectorApiRpmMetricsEndpoint)
   this.COLLECTOR_API_INCOMING_EDGE_METRICS = url.resolve(options.collectorApiUrl, options.collectorApiIncomingEdgeMetricsEndpoint)
   this.COLLECTOR_API_EXTERNAL_EDGE_METRICS = url.resolve(options.collectorApiUrl, options.collectorApiExternalEdgeMetricsEndpoint)
+  this.COLLECTOR_API_HEALTHCHECK = url.resolve(options.collectorApiUrl, options.collectorApiHealthcheckEndpoint)
 
   this.collectorLanguage = options.collectorLanguage
   this.apiKey = options.apiKey
@@ -96,6 +97,16 @@ CollectorApi.prototype.sendRpmMetrics = function (data) {
   this._send(url, this._withInstanceInfo(data))
 }
 
+CollectorApi.prototype.ping = function () {
+  if (!isNumber(this.serviceKey)) {
+    debug('Service id not present, cannot do healthcheck')
+    return
+  }
+
+  var url = util.format(this.COLLECTOR_API_HEALTHCHECK, this.serviceKey)
+  this._send(url, this._withInstanceInfo({}))
+}
+
 CollectorApi.prototype.sendApmMetrics = function (data) {
   if (!isNumber(this.serviceKey)) {
     debug('Service id not present, cannot send metrics')

lib/agent/api/index.spec.js

@@ -21,6 +21,7 @@ describe('The Trace CollectorApi module', function () {
     collectorApiEdgeMetricsEndpoint: '/service/%s/edge-metrics',
     collectorApiIncomingEdgeMetricsEndpoint: '/service/%s/edge-incoming',
     collectorApiExternalEdgeMetricsEndpoint: '/service/%s/edge-external',
+    collectorApiHealthcheckEndpoint: '/service/%s/healthcheck',
     system: {
       hostname: 'test.org',
       processVersion: '4.3.1',

lib/agent/healthcheck/index.js

@@ -0,0 +1,20 @@
+function Healthcheck (options) {
+  var _this = this
+
+  this.collectorApi = options.collectorApi
+  this.config = options.config
+  this.healthcheckInterval = this.config.healthcheckInterval
+  this.interval = setInterval(function () {
+    _this.ping()
+  }, this.healthcheckInterval)
+}
+
+Healthcheck.prototype.ping = function () {
+  this.collectorApi.ping()
+}
+
+function create (options) {
+  return new Healthcheck(options)
+}
+
+module.exports.create = create

lib/agent/healthcheck/index.spec.js

@@ -0,0 +1,22 @@
+var expect = require('chai').expect
+
+var Healthcheck = require('./')
+
+describe('The Healthcheck module', function () {
+  it('pings the collector', function () {
+    var collectorApi = {
+      ping: this.sandbox.spy()
+    }
+
+    var healthcheck = Healthcheck.create({
+      collectorApi: collectorApi,
+      config: {
+        healthcheckInterval: 1
+      }
+    })
+
+    healthcheck.ping()
+
+    expect(collectorApi.ping).to.be.called
+  })
+})

lib/agent/index.js

@@ -7,6 +7,7 @@ var assign = require('lodash.assign')
 
 var CollectorApi = require('./api')
 var Metrics = require('./metrics')
+var Healthcheck = require('./healthcheck')
 var consts = require('../consts')
 var ReservoirSampler = require('./reservoir_sampler')
 
@@ -34,6 +35,11 @@ function Agent (options) {
     config: this.config
   })
 
+  this.healthcheck = Healthcheck.create({
+    collectorApi: this.collectorApi,
+    config: this.config
+  })
+
   this.rpmMetrics = Metrics.rpm.create({
     collectorApi: this.collectorApi,
     config: this.config

lib/config.js

@@ -2,6 +2,7 @@ var url = require('url')
 var config = {}
 
 config.collectInterval = 2 * 60 * 1000
+config.healthcheckInterval = 10 * 1000
 
 config.collectorLanguage = 'nodejs'
 config.collectorApiUrl = 'https://trace-collector-api.risingstack.com'
@@ -12,6 +13,7 @@ config.collectorApiRpmMetricsEndpoint = '/service/%s/rpm-metrics'
 config.collectorApiEdgeMetricsEndpoint = '/service/%s/edge-metrics'
 config.collectorApiIncomingEdgeMetricsEndpoint = '/service/%s/edge-incoming'
 config.collectorApiExternalEdgeMetricsEndpoint = '/service/%s/edge-external'
+config.collectorApiHealthcheckEndpoint = '/service/%s/healthcheck'
 
 config.configPath = 'trace.config'